Chemical composition as per ISO 898-1 for typical grades
Class | Material and Treatment | C min. | C max. | P max. | S max. | B max. | Tempering temp. [°C] |
---|---|---|---|---|---|---|---|
8.8 | carbon steel with additives (e.g. b, mn or cr) quenched and tempered | 0.15 (d) | 0.40 | 0.025 | 0.025 | 0.003 | 425 |
8.8 | carbon steel quenched and tempered | 0.25 | 0.55 | 0.035 | 0.025 | 0.003 | 425 |
10.9 | carbon steel with additives (e.g. b, mn or cr) quenched and tempered | 0.15 (d) | 0.35 | 0.025 | 0.025 | 0.003 | 340 |
10.9 | carbon steel quenched and tempered | 0.25 | 0.55 | 0.025 | 0.025 | 0.003 | 425 |
10.9 | carbon steel with additives (e.g. b, mn or cr) quenched and tempered | 0.20 (d) | 0.55 | 0.025 | 0.025 | 0.003 | 425 |
10.9 | alloy steel quenched and tempered (g) | 0.20 | 0.55 | 0.025 | 0.025 | 0.003 | 425 |
12.9 | alloy steel quenched and tempered (g) | 0.28 | 0.50 | 0.025 | 0.025 | 0.003 | 380 |
(d) in case of plain carbon boron steel with a carbon content below 0.25% (ladle analysis), min manganese 0.6% for 8.8 and 0.7% for 10.9
(g) alloy steel shall contain one of the following elements: chromium 0.30%, nickel 0.30%, molybdenum 0.20%, vanadium 0.10%
Mechanical and physical properties as per ISO 898-1 for typical grades
Mechanical or Physical Property | Class 8.8 (M16 and below) | Class 8.8 (above M16) | Class 10.9 | Class 12.9 | |
---|---|---|---|---|---|
Tensile strength (MPa) | nom. | 800 | 800 | 1000 | 1200 |
Tensile strength (MPa) | min. | 800 | 830 | 1040 | 1220 |
Stress at 0.2% non-proportional elongation (yield) (MPa) | nom. | 640 | 640 | 900 | 1080 |
Stress at 0.2% non-proportional elongation (yield) (MPa) | min. | 640 | 660 | 940 | 1100 |
Stress under proof load (MPa) | nom. | 580 | 600 | 830 | 970 |
Elongation after fracture for machined test piece (%) | min. | 12 | 12 | 10 | 8 |
Reduction of area after fracture for machined test piece (%) | min. | 52 | 52 | 48 | 44 |
Impact strength, charpy v-notch (J) | min. | 27 | 27 | 27 | (under investigation) |
Hardness requirement as per ISO 898-1 for typical grades
Hardness Scale | Class 8.8 (M16 and below) | Class 8.8 (above M16) | Class 10.9 | Class 12.9 |
---|---|---|---|---|
Vickers, HV | 250-320 | 255-335 | 320-380 | 385-435 |
Brinell, HB | 238-304 | 242-318 | 304-361 | 366-414 |
Rockwell, HRC | 22-32 | 23-34 | 32-39 | 39-44 |
↫ Go backWhilst the information is provided in good faith, Andrews Fasteners Ltd are not under any responsibility or liability in respect of errors or information that was found to be incorrect or for any reliance the user may place on it.